Wikipedia
Spookyfish
"Spookyfish" is the fifteenth episode of the second season of the animated television series South Park, and the 28th episode of the series overall. "Spookyfish" originally aired in the United States on October 28, 1998 on Comedy Central. It was the season's Halloween special, featuring the "spooky" theme of having pictures of Barbra Streisand in the screen corners, accompanied with the words "Spooky Vision" (in response to Streisand's negative reception to the season one episode " Mecha-Streisand").
According to the official website and the DVD set, the episode's title is "Spookyfish". Other sources occasionally refer to it as "Spooky Fish".